Bump gatsby-image from 2.5.0 to 2.6.0

Bumps [gatsby-image](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-image) from 2.5.0 to 2.6.0.
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-image/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/gatsby-image@2.6.0/packages/gatsby-image)

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -67,7 +67,7 @@
     "classnames": "^2.2.6",
     "copy-to-clipboard": "^3.3.1",
     "find-package-json": "^1.2.0",
-    "gatsby-image": "^2.5.0",
+    "gatsby-image": "^2.6.0",
     "gatsby-plugin-canonical-urls": "^2.4.0",
     "gatsby-plugin-favicon": "^3.1.6",
     "gatsby-plugin-polyfill-io": "^1.1.0",